Resources -
3D Inserts FAQs

A: Cell culture is a very useful and widely used technique in stem cell research,
(bio)pharmaceutical development, cell biology, toxicology, bioengineering and tissue
engineering fields for observing and studying cells and their interactions with
pharmaceuticals, biological factors and biomaterials in vitro.

A: While culturing cells in two dimensions (2D) is a convenient method for preparing,
observing and studying cells and their interactions with pharmaceuticals, biological
factors and biomaterials in vitro, it does not mimic the cell growth fashion in
vivo. In real living body, cells are often growing in three dimensional (3D) and
building three dimensional living tissues or organs.

A: Emerging evidence showed that 3D cell culture systems in vitro would offer the
following advantages

1. Facilitate the understanding of structure–function relationship in normal and
pathological tissue conditions. Studies have shown that human annulus disc cells
cultured in 3 dimensional gel systems showed different morphology than those cultured
in 2D. These cells cultured in 3D showed increased proteoglycan synthesis compared
to monolayer grown cells, and formation of multi-celled colonies with extracellular
matrix deposited around and between cells. Furthermore, the human annulus disc cells
cultured in 3 dimensional showed the evidence of Type I and II collagen production
which was not found in mono-layer cell culture.

In vitro animal cell growth in 3D promotes normal epithelial polarity and differentiation.
Cells move and divide more quickly and have a characteristically asymmetric shape
compared with that of cells in living tissue.

2. 3D cell culture is a better model for studying the interactions between cell
and growth factors as well as cell and therapeutic agents. For example, a three
dimensional cell culture of cancer cells allows the exploration of many basic questions
related to cancer biology, as receptors for tumor development growth factors are
expressed in different ways in comparison to the standard 2 dimensional tissue culture
plates. For breast cancer, 3 dimensional culture provides a model system for understanding
the regulation of cancer cell proliferation and for evaluation of different anticancer
drugs. There is a substantial amount of evidence that cells growing in 3D culture
are more resistant to cytotoxic agents than cells in monolayer or dispersed culture.
Many studies have demonstrated an elevated level of drug resistance of spheroids
culture compared with cells in monolayer. Initially, investigators attributed drug
resistance of spheroids to poor diffusion of the drugs to interior cells but now
it has been proved that only 3 dimensional culture accounts for drug resistance
rather than mere inaccessibility to nutrients. Further study confirmed that 3D culture
is a better model for the cytotoxic evaluation of anticancer drugs in vitro.

3. 3D cell culture systems in vitro can facilitate the understanding of structure–function
relationship in normal and pathological conditions. It is now well accepted that
bone and cartilage-derived cells behave differently in 3D than in a 2D environment
and that the 3D culture systems in vitro are mimicking the in vivo situation more
closely than the 2D cultures. In a recent study, three human osteogenic cell lines
and normal human osteogenic (HOST) cells were cultured in 3D hydrogel matrix. It
was demonstrated that osteosarcoma cells proliferate as clonogenic spheroids and
that HOST colonies survive for at least 3 weeks. Mineralization assay and gene expression
analysis of osteoblastic markers and cytokines indicate that all the cells cultured
in 3D in this hydrogel matrix exhibited a more mature differentiation status than
cells cultured in monolayer on plastic cell culture plates.

4. 3D culture is a better technique for stem cell expansion. Human Embryonic Stem
Cells (hESC), when culture in 3D for expansion, showed a much higher cell number
after 30 day expansion, compared to 2D expansion in cell culture plate. Expanded
hESC are able to differentiate into representatives of the three germ layers: ectoderm,
endoderm, and mesoderm.

A: Similar to tissue-engineered scaffolds, the products are fabricated using the
state-of-the-art precision micro-fabrication technology. Instead of using biodegradable
materials as in tissue engineering, our cell culture scaffolds will be fabricated
using non-biodegradable materials with controlled porosity and pore size. Cells
will be growing freely throughout the 3D structure of the scaffold, thereby enabling
3D cell culture.

A: 3D Biotek is developing a series of innovative 3D cell culture products to help
our customers to achieve the following objectives:

Reduce animal testing

Yield more predictive data from in vitro study

Improve cell culture efficiency

Increase the production yield of cytokines, antibodies, and other biological molecules.

Reduce cost and time to identify new drug candidates

Reduce time to market

As a publication in journal Nature pointed out: the benefits of the technique
are so self-evident that little marketing will be needed to persuade the uninitiated
to move up a dimension, just as soon as the issues of convenience are resolved.

Convenient to use - The products are sterilized and ready to use, just like the
way of using cell culture dish/plates/flasks. No further preparation is needed.

100% open porosity - The pores of the products are 100% open, therefore, cells can
be seeded easily throughout the scaffolds, and the nutrient and cell metabolism
waste can be exchanged easily. This feature allows the products particularly useful
in conducting dynamic cultures.